Corresponding author: Dmitry E. Klimenko
(listopad19531@mail.ru)
Keywords: forest hydrology; mapping, GIS-technologies;
forest science, rainfall floods, modeling, canopy rainfall interception
Abstract. Metering of actual volume of rainfall flowing under
the canopy of the taiga zone trees is a crucial factor of correct
calculation of the maximum water flow in small rivers. This is because
only part of the rainfall that has fallen through the forest canopy and
reached the soil joins the river runoff. The article presents the
results of physical simulation of maximum rainfall retention on the
crowns of taiga stands of the Middle Urals () as well as the results of
mapping the values of interception and its determinants for the model
watershed. The findings of this study help to understand how the maximum
flood runoff is formed, and this knowledge is essential today as various
hydrological models are being developed. The authors have mapped the
species composition, height, and density of forest crowns based on
satellite imagery, air photographic mosaics, and field research
findings. The technique of mapping rainfall losses on vegetation has
been developed, which could be of great interest for improving the
quality of hydrological models used in global practice.
Rainwater is retained on the crowns in drip form (drop size ranges from
10.6 to 18.6 mg). Specific water retention (mass per unit of the leaf
surface area) depends on the roughness of laminae (or needles). Absolute
retention of drops on the crowns depends on the leaf surface area and
rainfall intensity. The maximum mass of water retention on the crowns of
detached deciduous trees is up to (3.0- per projection area of the
crown), whereas that of coniferous trees ranges from 24.8 to (1.9 to ).
Based on the developed map model of rainfall interception, genetic
methods were used to calculate the hydrograph of a single rain flood for
the model watershed of the Reshetka river. Taking into account the
rainfall loss through crown retention, it is possible to reduce
calculation errors of maximum flood water flow from 126 to 25%.